Text preview for : 25gs3-p68~p75(Repair).pdf part of Philips 25gs3-p68~p75(Repair) Philips Monitor CD 2001 Monitor CD 2001 E-MANUALS Philips crt 107p2 Pdf 25gs3-p68~p75(Repair).pdf
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68 107P2 CM 25 GSIII Repair Flow Chart
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A. Power Supply Failure
1. Symptom : check 7106
no startup sound check 7106 pin1 check 7106 check 7106
Ok Ok pin 8=2.4V Ok
LED light off 100V 2V pin4 output ?
3131=24kohm
NO NO NO Ok
check check check
replace 7106 6165/3113/ NO
1101/6102/ 3121/3122/1106
7105 3124/2121/3136 3114/7105
check
check
replace 7106 3128/6107
pin6>8V
/6115
Turn power off
2. Symptom :
check the resistance for
hicup mode with check 7106 check 7106
all output voltages+180, OK
startup sound or pin 6 < 13.5V pin 5 < 0.5V
80,13,-13,-6.1,+5,+8 V
blinking LED
check 6148~6159 short?
No No
OPP possibly active
check check 7103 OVP possibly active
No check 3115,3116,
7157/7155/7113/7154 open circuit check 6115
3117,3118,6116,3127
OK
OK
replace 5101 replace 5101
7106 pin14 OOB
check 7153 pin3 check 7153 pin1
Ok No possibly active
voltage dip 12V< pin1 < 15V
short 7155 pinC
No
Ok
check check check CPU pin 22
+5V loading current 6162/3170/3171 and 7805 emitter
3173/7157/2165
check check 7105 check
3. Symptom:
frequency Ok drain waveform No 6103/3111/6103/
abnormal sound
F=72.5KHZ right? 6108/2128/3112
No Ok
check
replace 5101
3131=24K
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Repair Flow Chart (Continued) 107P2 CM 25 GSIII 69
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rough check for R, G, B
B. Video 1. video input= 0.7V
Repair Flow 2. 7301video output =2.5V check blanking
3. 7701 video output= 35V swing 7503 pin16
Ok
check
1.Symptom :
R,G,B output
(with white pattern) check heater check check
Ok No 30<2725<80
no picture =-6.1V EHT=25KV VG1 < -150V
30<2733<80
green LED on
30<2753<80
No
Ok
check Xray prot.
7503 pin2 check DC restoration
check
7722,7732,7752
VG2 > 350V
7721,7731,7751
check blanking
7503 pin16
Ok
2.Symptom :
no video (or dim), check Vg1 check cathod
No turn down Vg2
only raster with/without retrace line Vg1 = 0V +80V/+180V
green LED on
check 7301 check 7701 check 7701
check 7301 pin24
Ok pin 6,8,10 pin8,9,11 pin 1,3, 5
2V< ABL < 5V
input swing input swing output swing
No Ok
replace IF
check 7301 replace 7701
cable
pin11 FLB
check check 7301
No Ok replace 7301
7503 pin16 pin5 CLBL
3. Sympton : check check 7304
check 7301
no OSD or No 7304 pin10 pin2 VCO
pin 2,3,4 input
OSD out of sync. VFLB pin3 RP
Ok
check check check 7304 check 7304
7304 pin12 Ok Ok
7301 pin1 pin5 HFLB pin 7,8(IIC)
No No
replace 7301 replace 7304
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70 107P2 CM 25 GSIII Repair Flow Chart (Continued)
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C. Horizontal deflection
output repair flow :
1. Symptom : check Hsync check Hsync check Hsync check Hsync
without
7604 base 7605 gate 7503 pin8 7503 pin6
H-deflection.
No
refer 7503 check list
or replace 7503
check
2. Symptom : check 7503
7608/7607/ refer 7503
East /West pin11
7606 check list
corr. parabola exist
parabola exist
3. Symptom : enter factory mode check
check 7611
H-linearity check linearity data 3622/3625/
pin 5,6,7
(full freq. range) in eeprom 7609 collector
refer cpu
check
check list
7609 replace 7611
check cpu
pin 4,5,6
check check cpu
4. Symptom : check check 7611
3684/3686 7801 pin38
rotation 7626,7627 pin 1,2,3
/3681 control range
check check cpu
5. Symptom : check
7607 collector 7801 pin2
H_dc shift 7608,7610
7606 emitter control range
enter OSD
6. Sympton : check check check
function
Focus 7631collector 7503 pin 32 7624/3655/5609
disable moire
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Repair Flow Chart (Continued) 107P2 CM 25 GSIII 71
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basic check
D. Vertical Deflection Failure
+13/-13V
Symptom :
check check
one horizontal line
7503 Ok +78V,
V_size is abnormal pin 12, 13 good?
too large/small (small)
No Ok
replace
7503
check 7404
pin1,pin7 ramp
exist ?
No
check
3401,3402
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72 107P2 CM 25 GSIII Repair Flow Chart (Continued)
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E. CPU check cpu pin 6/pin 5=5V
Basic Check
check list pin 8/pin 9=12MhZ
check pin 4
4. H-linearity
pwm from 0V to 5V
check pin2
2. H-Centering
pwm from 0V to 5V
check pin19
19. Blank normal : low
change timing : Hi
Hor. Freq.(KHz) Q5 Q4 Q3 Q2 Q1
~33.24 0 0 0 0 0
33.24~36.51 0 1 0 1 0
36.51~40.60 0 1 1 0 0
14, 13, 12, 11,10 check Q1-Q5 40.60~45.07
45.07~47.62
1
1
0
0
0
0
0
1
0
1
(Q5,Q4, Q3, low : 0
47.62~51.49
51.02~55.07
1
1
0
0
1
1
1
1
0
1
Q2,Q1) hi :1 55.07~61.96 1 1 0 0 0
S-cap switch
61.96~66.29 1 1 0 1 0
66.29~71.00 1 1 0 1 1
71.00~76.00 1 1 1 0 0
76.00~82.96 1 1 1 0 1
82.96~89.00 1 1 1 1 0
89.00~0xffff 1 1 1 1 1
check pin 3
3. ABL-Adj
pwm from 0V to 5V
check pin18
18. Hunlock normal=Hi
blank=low
pin27 pin20
27, 20 P.S. normal hi hi
check pin20/27
LED standby low hi
off low low
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Repair Flow Chart (Continued) 107P2 CM 25 GSIII 73
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check
22. Degauss active=hi
no active=low
check
5. Reset
5V
check
37. Brightness
pwm from 0V to 5V
check
38. Rotation
pwm from 0V to 5V
check key
23. Keypad
Enter,+,-,bri,con keys
check pin 24
1.no H/V sync & IF cable pin5 floating - show msg.
2.H/V sync exist & IF cable pin5 to ground - normal
24. Selftest
3.H/V sync non-exist & IF cable pin5 to gnd - power saving
4.connect a 15k resistor with IF cable pin5 - factory mode
5.connect a 5k1 resistor with IF cable pin5 - burn in mode
check idle status
25, 26. DDC bus sda=pin 25=hi
scl=pin 26=hi
check
check idle status 7804 M24C16-BN6
31, 32. IIC bus sda=pin 31=hi 7503 TDA4841
scl=pin 32=hi 7304 MTV018-27
7301 TDA4886
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74 107P2 CM 25 GSIII Repair Flow Chart (Continued)
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Basic check
F. TDA4841 Vcc=pin9=pin10=12V
Vcc > 9V
Check List gnd =pin7=pin25=0v
during startup
1. HFLB pin16
if no exist
(from H.defl) CLBL=hi
pin17 = Hunlock = floating
pin30 = Hpll2 = 0V
pin6 = HDRV = floating
2. Xray
if active pin8 = BDRV = flaoating
(from LOT)
pin12 = Vout1 = floating
pin13 = Vout2 = floating
pin16 = CLBL= Hi
a pin3 amplify pin5 and it compare to pin4
inhibit pin6 output
b. pin4 generate the saw_tooth wave
3.4.5.6 B+ control if pin3 is pulled to
c. pin5 input voltage for the square output waveform
ground by 7508
d. pin6 pwm output to 7601 gate & 7602 base
to H_deflection.
8. HDRV
7602 base
to H_deflection
11.EWDRV east/west control
differential input
12,13 Vout1/Vout2
to 7404 pin 1, 7
14,15 the input sync from
Vsync,Hsync cpu pin 40,41
Vertical blank will be activated = hi
1.pin30 = softstart pll2 = 0V
2.pin26 = pll1 is unlock in searching mode
16. CLBL
3.pin1 = HFLB no exist
4.pin2 = Xray once actived
5.pin10 = Vcc < 9V
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Repair Flow Chart (Continued) 107P2 CM 25 GSIII 75
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Hunlock pin is floating while pll1(pin26) is
17. Hunlock
unlock in searching mode
18. IIC sda = hi initial fail could be these of IC
19 IIC scl = hi 7503,7301,7304,7804
20 asymmetry EW to 7503 pin30
output for soft start
compensate for the V_size
21 EHT_compen.
owing the load variation
22,23,24 pin22 determin the AGC
50Hz< freq. <160Hz
VAGC,VREF,VCAP pin23,pin24 determin frequency
pin26 determin the
26,27,28,29 pll1 loop filter
30K Hpll1,Hbuf,Href, Hcap pin 27,28,29 H-Freq
working range
1.compare the HFLBand control the phase of HDRV
30. PLL2
2.softstart
31 EHT_compen. compensate for the H_size owing the load variation
32. Focus to 7642 for the V dynamic focus
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